4 
Creusta.—Shell sessile, fixed, orbicular, convex-conical, quadrivalve: valves unequal, 
united together, sutures distinct. Operculum internal, quadrivalve. 
Plate I. Fig. 16. (a) C.verruca. Outside. . (Lepas verruca—Linn.) 
(6) Inside. 
Pyrcoma.—Shell sessile, univalve, rather globular, ventricose, convex above; apex per- 
forated: aperture small, elliptical. Operculum quadrivalve. 
Plate I. Fig. 17. (a) P. crenata. Outside. 
(6) Inside. 
ORDER II.._.PEDUNCULATED CIRRHIPEDA. 
THE body is supported by a moveable, tubular pedicle, having the base fixed on marine 
substances.—This Order consists of Two Divisions, viz. 1. The shell composed of conti- 
guous pieces. 2. The shell composed of distant pieces. 
Division 1.— Shell composed of Contiguous Pieces. —2 GENERA. 
ANATIFERA.—Shell compressed at the sides, composed of five valves, which are contigu- 
ous and unequal; the lower side valves the greatest. 
Plate I. Fig. 18. A. levis. (Lepas anatifera—Linn.) 
Po..iciPEs.—Shell compressed at the sides, multivalve, valves rather contiguous, une- 
qual; in number, thirteen or more: the lower side valves smallest. 
Plate I. Fig. 19. P. cornucopia. (Lepas pollicipes.—Linn.) 
Division 2.— Shell composed of Distant Pieces. —2 GENERA. 
Crneras.—Shell composed of five testaceous oblong valves, separate, not covering the 
whole of the body: two at the sides of the aperture; the others on the back. 
Plate II. Fig. 3. C. vittata. [Icon.—Wood’s Conch. Tab. XII. Fig. 2.] 
Or1on.—Shell composed of two* testaceous small semi-lunate separate valves, adhering 
near the sides of the aperture. 
Plate Il. Fig. 4. O. Cuvieri. (Lepas aurita.—Linn.) [Icon.—Wood’s Conch. Tab. XII. Fig. 4.] 
* This Shell has sometimes five testaceous valves; sometimes two testaceous, and three horny valves, 
Vide Sowerby’s Genera. 
